1. Field of the Invention
This invention relates generally to the field of pressure relief and more specifically to a machine with an ejector for affecting pressure relief.
2. Description of the Related Art
A requirement for pressure relief began when the first vessel was heated to develop steam. This dates back at least to the time of the ancient Greek scientist Hero of Alexandria who experimented with jet propelled rotary steam engines in the first century A.D., whereby it was established that heating a fluid in a closed container will cause increased pressure within the container. If the pressure exceeds the strength of the container, the container will explode with obvious undesirable consequences. Means to dissipate excess pressure, therefore, have long been devised and are well known. But, heretofore, numerous disadvantageous characteristics have been inherent in known pressure release means.
For example, those means that are cheap and uncomplicated tend not to be capable of dealing with extremely high pressures. Also, many designs require complicated structures with parts precisely cast or machined so that they are extremely difficult and expensive to make. Some such intricate constructions will foul easily should bits of solid material flow through them.
Numerous designs require fusible or frangible elements which necessitate the replacement of the entire valve or the disassembly and reassembly of the valve after activation, during which time the process or system being regulated must be shut down for extended periods. Other designs require elements such as, but not limited to, explosives, motors, solenoids, or pressurized gas, which are independent of the medium being regulated, to activate the valve.
Sundry designs also require complex pressure sensing means communicating with servo mechanisms to activate valves. Furthermore, because of characteristics inherent in known designs, the stated set pressure frequently varies from the actual set pressure by significant amounts. Obviously, if the actual set pressure is higher than the stated set pressure, a given valve might not activate at a pressure low enough to prevent damage to a system or process, while if the actual set pressure is too low, a process or system may be interrupted unnecessarily.
In addition, many designs require dampening means to prevent flutter.
The instant disclosure overcomes these disadvantages thusly advancing the art of pressure relief.
U.S. Pat. No. 7,007,715 B2 by Nakayama et al. discloses a pressure relief valve having a shaft part mounted coaxially within an outlet conduit and a valve element of flexible material having a seal lip contacting the exterior of the shaft part and a base portion contacting the interior of the outlet conduit. In addition, Nakayama et al. teach an extension spring disposed circumferentially about a portion of the valve element so as to press the seal lip against the exterior of the shaft part and teaches against travel of the valve element within the outlet conduit. This, in combination with the base portion's being in contact with the interior of the outlet conduit, blocks flow through the outlet conduit.
Other embodiments taught by Nakayama et al. are effectively turned inside out. The valve body is disposed so that one portion is supported by the shaft part. Another portion comprises a cap over the end of the outlet conduit. Part comprising a seal lip is held by an extension spring to the exterior of the outlet conduit. In all embodiments of Nakayama et al., the valve is opened when pressure within the outlet conduit is great enough to overcome the extension spring so that the seal lip may be forced away from the outlet conduit or the shaft part thusly releasing said pressure.
In contrast to Nakayama et al., the instant art teaches no spring that must be overcome in order for a valve to open. In additional contrast to Nakayama et al., the instant art teaches away from deforming a part of a valve element in order that pressure be allowed to escape between the valve element and the interior or exterior of an outlet. The instant art, instead, teaches deforming a valve element to an extent that it prevents the medium being regulated from leaking out between the valve element and the containing or supporting structure. In yet further contrast to Nakayama et al., the instant art teaches movement of a valve element within a bore with pressure release accomplished by alignment of openings in the valve element and the outlet conduit or exposure of said openings directly to the atmosphere, the area of said openings not limited to area less than the cross sectional area of the outlet conduit.
Furthermore, one may note that the volume of medium that may be released through the outlet conduit taught by Nakayama is limited by the shaft part and/or the shaft part with valve body affixed which substantially occludes the cross section of the outlet conduit. In contrast, the instant art, by accomplishing pressure release by means of the previously described alignment of holes or direct exposure to the atmosphere, allows, via nozzle effect, for an increased discharge through the same diameter outlet conduit. This is a significant advantage over Nakayama et al.
U.S. Pat. No. 6,820,652 by Gaydos et al. discloses a valve comprising a valve seat having inlet ports and outlet ports with a valve seal covering the ends of the inlet ports and exit ports and a housing to secure the valve seal to the valve seat such that there is clearance between the valve seal and the housing. The valve seal is elastomeric so that when pressure entering the inlet port is great enough, the seal will distend and uncover the ends of the inlet ports and outlet ports allowing pressurized medium to flow through the clearance between the valve seal and the housing and out.
In contrast to Gaydos et al., the instant art teaches embodiments comprising no valve seat. In additional contrast to Gaydos et al., the instant art teaches away from flow between a valve element and a housing. Instead, it teaches pressure relief by means of the movement within a bored structure of a valve element which aligns holes in the valve element with holes in the bored structure or exposes holes directly to the atmosphere. In further contrast to Gaydos et al., the instant art does not require that the inlet and exit ports have portions with diameters less than the housing. Thus, instant art of the same diameter as Gaydos et al. may affect the passage of much greater volume of medium and thus accomplish more rapid release of pressure, an advantage over Gaydos et al.
U.S. Pat. No. 4,846,810 by Gerber discloses a valve having a body covered by an elastomeric sheath which blocks inlet and outlet passages through the valve body. When pressure within the inlet ports is sufficient, the elastomeric sheath is forced away from the valve body so that medium may pass between the elastomeric sheath and the valve body via the inlet and outlet passages.
In contrast to Gerber, the instant art comprises no elastomeric sheath and teaches away from the passage of medium between a valve body and an outside surface. In additional contrast to the instant art, the cross sectional area of the outlet of Gerber must be substantially less than the cross sectional area of the valve body so that the maximum flow released by Gerber must be less than that of the instant art for a given valve body size, an advantage over Gerber.
U.S. Pat. No. 3,474,809 by Gordon discloses a valve having an element in the form of a flap held in place by frangible connection with an element. In addition, Gordon discloses a piston, powered by an explosive charge which, upon activation, breaks the frangible connections so that the valve may open. Gordon teaches activation by electrical signal triggered by a pressure sensing device and teaches away from operation of the valve by means of pressure within a valve assembly.
In contrast to Gordon, the instant art does not teach or require a flap type valve element, nor does it teach or require any frangible connection or explosive. The instant art teaches activation of the valve by action of pressure, within a valve assembly, of the medium being regulated, this also being contrary to Gordon.
U.S. Pat. No. 6,058,961 by Taylor discloses a piston valve having a valve seat and a pressure sensing means separate from the piston but communicating with the piston. In addition, Taylor teaches that the piston is of always equal slidable fit within a bore regardless of the pressure of the medium being regulated.
In contrast to Taylor, the instant art teaches no valve seat or any pressure sensing means separate from a valve element. In additional contrast to Taylor, the instant art comprises a valve element wherein the slidable fit varies in response to various levels of pressure.
U.S. Pat. No. 3,494,370 by Wahl et al. discloses a valve having an element held in closed position by frangible elements and opened by force of an explosive powered ram which breaks the frangible elements and forces the valve element to open position.
In contrast to Wahl et al., the instant art neither teaches nor requires any frangible element or ram. In additional contrast to Wahl et al, the instant art neither teaches nor requires explosive or any source of energy separate from the medium being regulated.
U.S. Pat. No. 6,851,445 B2 by Girouard discloses a pressure relief device having an inlet and an outlet, the inlet portion having a diameter greater than the outlet portion. Girouard further discloses a plug located in a bore between the inlet and outlet and a bonding material to hold the plug in a position until a pre-determined temperature is reached. In addition, Girouard requires the bore and the plug to have tapered portions.
In contrast to Girouard, the instant art neither teaches nor requires an inlet with a diameter different than the diameter of the outlet. In additional contrast to Girouard, the instant art teaches embodiments requiring neither a bore nor a plug having tapered portions. In further contrast to Girouard, the instant art neither teaches nor requires a temperature sensitive bonding material to hold any element in place.
U.S. Pat. No. 6,994,101 B2 by Freiler discloses a pressure relief valve comprising a fusible element and heat conducting elements to conduct heat from a medium in a vessel to the fusible element which melts and releases pressure at a pre-determined temperature.
In contrast to Freiler, the instant art neither teaches nor requires any fusible element nor any heat conducting elements. In additional contrast to Freiler, the instant art is not dependent upon temperature of any medium for activation.
U.S. Pat. No. 7,033,387 by Zadno-Azizi et al. discloses a structure to hold a valve element held in place in a conduit by friction. In addition, Zadno-Azizi et al. teaches a stationary flow control mechanism independent of but, communicating with, the friction causing structure and a valve element.
In contrast to Zadno-Azizi et al., the instant art neither teaches nor requires a flow control mechanism operating independently of the friction causing mechanism but to the contrary teaches that the aforesaid are one in the same. In additional contrast to Zadno-Azizi et al., the instant art teaches flow control by movement of a valve element within a conduit.
U.S. Pat. Nos. 6,978,799 B2 and 6,209,561 B1 by Kugelev et al. disclose pressure relief valves, each having a piston valve element within a bore which defines an upper chamber and a lower chamber. The upper chamber communicates with a pressurized fluid other than the fluid being regulated. This biases the piston valve element in closed position. When the pressure in the lower chamber reaches a pre-determined level, the piston valve element is forced into open position and the pressurized fluid in the upper chamber is transferred to the lower chamber to delay return of the piston valve element to closed position.
In contrast to Kugelev et al., the instant art neither teaches nor requires the action of any media other than the one being regulated and neither teaches nor requires transfer of any media from one chamber to another to delay return of a valve element to closed position. In additional contrast to Kugelev et al., the instant art teaches embodiments having no biasing means.
U.S. Pat. No. 6,935,616 B2 by Baumann teaches a plug valve wherein the plug has stepped diameters and wherein the plug is slidable within a bore having stepped diameters with said stepped diameters comprising valve faces on the plug and valve seats in the bore. In addition, Baumann teaches and requires means to equalize pressure on both sides of the plug and teaches slanted inlet and outlet passages. Also, Baumann teaches an actuating device independent of whatever media the valve may regulate and a bonnet.
In contrast to Baumann, the instant art teaches embodiments having no stepped diameters of any elements and teaches embodiments without valve seats. In additional contrast to Baumann, the instant art neither teaches nor requires equalized pressure on both sides of any valve element but teaches unequal pressure on opposing sides of the valve elements. In further contrast to Baumann, the instant art requires no activating agency other than that of whatever media may be regulated and does not require slanted inlet or outlet ports and teaches embodiments having no bonnet.
U.S. Pat. No. 4,673,162 by Lachmann discloses a flow control valve having a valve chamber and a control chamber with a valve body disposed there between and having a valve face exposed at the inlet of the valve, said valve body further comprising a control body disposed in the control chamber and having a control face and a counter pressure face with the counter pressure face having a surface area larger than that of the valve face. The control body divides the control chamber into a control compartment at the control face and counter pressure compartment at the counter pressure face. In addition, Lachmann teaches pressurization of the control chamber by means of communication with separate pressurized control medium at the inlet. Further, Lachmann discloses an electrically motivated valve activation device such as a solenoid.
In contrast to Lachmann, the instant art neither teaches nor requires communication in order to transfer pressure from one side of a valve element to another in order to affect movement of said valve element. In additional contrast, the instant art neither teaches nor requires electricity nor any force other than direct contact with the medium being regulated.
U.S. Pat. No. 6,918,409 B1 by Parker discloses a spool valve having increased clearance between the spool and the inside of a conduit, a spring, and an electrical and magnetic activating device.
In contrast to Parker, the instant art teaches away from clearance between a valve element and the conduit in which it is disposed, teaches embodiments having no spring, and neither teaches nor requires the agency of electricity and/or magnetism nor any other activating force other than that of the medium being regulated.
U.S. Pat. No. 6,918,407 B2 by White et al. discloses a valve assembly having a valve element with an upper end communicating with a pneumatic control chamber and a lower end communicating with a fluid. Also, disposed between the valve element upper end and the pneumatic control chamber is an upper chamber which communicates with the fluid. The pneumatic control chamber is pressurized preceding use and exerts a force on the valve element biasing it into closed position. When pressure of the fluid exceeds the pressure of the pneumatic control chamber, the valve is forced open.
In contrast to White et al., the instant art teaches embodiments having no biasing means and neither teaches nor requires communication between one side of a valve element and another. In additional contrast to White et al., the set point of the instant art may depend only upon the valve element itself and not on any complicated structure communicating with it.
U.S. Pat. No. 3,847,412 by Mattson discloses a ballistic missile traveling freely, substantially without any impediment, within a tube having apertures disposed radially and transversely. The missile is hollow and is propelled within the tube by release of pressurized gas aft of the missile. The missile has apertures radially disposed about its forward end so that the pressurized gas may be released when said apertures align with the holes in the steel tube. The missile allows gradual increase in the quantity of gas release upon initiation of gas inflow into the steel tube and allows for gas release immediately upon introduction into the steel tube.
In contrast to Mattson, the instant art teaches away from gradual increase in quantity released but rather teaches substantially instantaneous release of maximum quantity and pressure. In additional contrast to Mattson, the instant art teaches away from release of material upon initial exposure of a valve element to said material but rather teaches a substantial set pressure below which no material is released. In additional contrast to Mattson, the instant art teaches a valve element frictionally fixed within a conduit with free movement possible only above substantially high set pressure.
U.S. Pat. No. 4,248,257 by Hardesty teaches a valve having an element held in closed position by an explosive bolt. Upon pressure activation of the valve, an electrical pulse activates an explosive which breaks the bolt and the element is allowed to move into open position.
In contrast to Hardesty, the instant art neither teaches nor requires any breakable or disintegratable elements and neither teaches nor requires explosives or electricity.
U.S. Pat. Nos. 6,637,448 B2 by Naab et al.; 4,579,136 by Oman et al.; 4,003,395 by Tyler; and 3,548,848 by Stichling disclose valve assemblies having valve elements held in position by frangible elements which are released by forces generated either by explosions or discharge of high pressure gas which break the frangible elements and force the valve elements to move. In no case is the activating force derived from the medium being regulated by the valves. In addition, Stichling teaches a second explosive charge which will return the valve element to its original position after being displaced by a first explosive charge.
In contrast to the above, the instant art teaches no frangible elements which must be broken nor any explosive charge or compressed gas charge or any activating agency independent from the medium being regulated.
U.S. Pat. No. 3,141,470 by La Fontaine teaches a valve having an element held in place by frangible connections. The valve element is moved by a piston powered by an explosive charge which causes the piston to break the frangible elements. In addition, La Fontaine discloses means to relieve pressure behind the piston after detonation of the explosive charge and means to prevent contact of the explosive gasses generated by explosion with the medium being regulated by the valve.
In contrast to La Fontaine, the instant art comprises no explosive charges, no piston which moves a valve element, no frangible elements, no pressure release means for gasses generated by an explosion, and no means to keep separate the explosive gasses and the medium being regulated. In further contrast to La Fontaine, the instant art neither teaches nor requires an activating agency using force separate from that of the medium being regulated.
U.S. Pat. No. 6,651,686 B2 by Scantlin et al. discloses an actuator system for a valve having a biasing element and a source of activating power separate from the medium being regulated by the valve. In addition, Scantlin et al. disclose a latch system which must be activated in order for the actuator to either open or close the valve.
In contrast to Scantlin et al., the instant art comprises no complicated separate activating device. In additional contrast to Scantlin, the instant art neither teaches nor requires any activating force derived from any source other than the medium being regulated, nor any latching mechanisms, and teaches embodiments having no biasing means.
U.S. Pat. No. 3,529,624 by Cryder et al. discloses a valve having a valve element with opposing portions comprising different surface areas, a dampening means, a biasing means, and a portion of the valve element which must communicate with a valve seat in order for the valve to close.
In contrast to Cryder et al., the instant art teaches embodiments having no biasing element. In additional contrast to Cryder et al., the instant art neither teaches nor requires dampening means nor opposing sides of a valve element having different surface areas. In additional contrast to Cryder, the instant art teaches embodiments having no valve seat.
U.S. Pat. No. 3,202,177 by Klein et al. discloses a pressure regulating valve having an element permanently slidable within a bore and having a biasing element.
In contrast to Klein et al., the instant art teaches embodiments having no biasing elements and teaches away from permanent slidability of an element within a housing, but teaches a valve element constrained by friction between the valve element and the housing.
U.S. Pat. No. 4,859,155 by Laqua discloses a displacement pump bypass valve having a spring which urges a piston against a valve seat. In addition, Laqua discloses an activation means having an expansion chamber, the volume of which is variable by means of a modulator disc in communication with a modulator spring.
In contrast to Laqua, the instant art teaches embodiments having no springs and embodiments having only one spring. In additional contrast to Laqua, the instant art neither teaches nor requires an expansion chamber nor any means to vary the volume thereof. In further contrast to Laqua, the instant art teaches embodiments having no valve seat or elements which must communicate with same.
U.S. Pat. No. 6,622,752 B2 by Kushida et al. discloses a pressure relief valve having an element which must communicate with a valve seat, a biasing element for the valve element, and a means to adjust the set point by deforming the valve housing by force from the outside which in turn changes the tension on the biasing element.
In contrast to Kushida et al., the instant art teaches embodiments having no biasing element, and neither teaches nor requires the deformation of a housing in order to vary the set point. In additional contrast to Kushida et al., the instant art teaches embodiments having no valve seat.
U.S. Pat. No. 6,651,696 B2 by Hope et al. teaches a pressure relief valve having a valve element slidable in a bore. In addition, the valve element is biased by at least one spring. Also, Hope et al. teaches a valve element having sealing assemblies biased against outlets. In addition, Hope et al. teach additional structures such as an internal passage and a valve element having stepped diameters. Further, Hope et al. teaches against friction between the valve element and the internal passage sufficient to prevent the movement of the valve element.
In contrast to Hope et al., the instant art teaches embodiments having no biasing element and teaches no embodiments having more than one biasing element. In additional contrast to Hope et al., the instant art teaches embodiments having no elements with stepped diameters and in all embodiments teaches friction between valve element and interior structure sufficient to prevent the valve element from moving. In further contrast to Hope et al., the instant art neither teaches nor requires any valve element having separate sealing assemblies.
U.S. Pat. No. 6,276,125 B1 by Tseng discloses a valve having a valve element which defines an upper chamber and a lower chamber with the valve element responsive to pressure in the upper chamber while subject to pressure in the lower chamber and upper chamber simultaneously. The area of the valve element surface defining the upper chamber must be different than the valve element surface defining the lower chamber. In addition, the valve element comprises a face which must communicate with a seat.
In contrast to Tseng, the instant art neither teaches nor requires a structure having two chambers wherein an activating force must communicate with opposite ends of a valve element either simultaneously or not simultaneously. In additional contrast to Tseng, the instant art does not depend upon a valve element having opposing structures with different surface areas. In yet further contrast to Tseng, the instant art teaches embodiments having no valve seat or corresponding communicating portion of a valve element.